Summary: Opioid Supplement to DA040213 Amidst increasing overdose deaths in the US, PA had the third highest rate with 44.3 deaths per 100,000 in 2017. Although overdose deaths strike all ages, races, ethnicities, genders, and socioeconomic strata, they are most prominent among White, male young adults and opioids are largely responsible. Non-prescribed use (i.e., diverted use) of prescription opioids was recently found to prospectively predict later use of heroin, highlighting the crucial importance of addressing diverted use of prescription opioids among young people. Initiatives have been launched to educate prescribers in recommended opioid prescribing principles and practices, yet it's unclear the extent to which these practices, such as those offered by the CDC, are effectively utilized. When researched, providers are only partly implementing recommended strategies or feel ill-equipped. Clarification of the extent to which prescribing providers for this highest risk age group are trained, knowledgeable, and able to successfully implement recommended diversion prevention strategies is critically needed. Our work on the prevention of stimulant diversion in primary care has made use of consultation and interviews with stakeholders including prescribers, and surveys, to develop a brief workshop for the busy primary care physician and their staff (DA035464, DA040213). This work, which has resulted in strong staff ratings of satisfaction (Molina et al., 2019, Academic Pediatrics), has unrealized potential for adaptation to the primary care and specialty environments for prevention of opioid diversion. We propose to extend our ongoing diversion prevention work with prescribers of Schedule II controlled substances (currently stimulants) to opioids. As young adults are an especially high-risk group and our work targets this developmentally at-risk age span, we propose to focus on opioid prescribing for the most at-risk 18-30 year old age range. Our research will involve 1) stakeholder and expert input informing 2) guided discussions with 100 physicians, physician extenders, nurses, and specialists (e.g., dentists, oral and orthopedic surgeons) and followed by 3) 100 surveys with these practitioners. Surveys will be adapted from our ongoing work to characterize prescribing practices and key constructs known to influence implementation (e.g., knowledge, attitudes, beliefs, perceptions of patient behavior and organizational resources and support). These aims will allow much-needed characterization of opioid prescriber behaviors and related constructs pertinent to the prevention of opioid diversion by their young adult patients. Results will inform the adaptation, for future testing, of our one-hour Stimulant Diversion Prevention workshop to the prevention of opioid diversion, in a format that has been well-received as highly feasible, and that has demonstrated (stimulant) diversion risk reduction in our first study with (college student) young adults. The proposed work relates to NIDA's DAT18-02 priority area of research on the development of innovative strategies to prevent opioid and prescription drug misuse as well as strategies to integrate sustainable, evidence-based prevention interventions and approaches into healthcare.